Wheels - There are a few possibilities here.Since
all wheels will be ground against, use rubber coated. You can use
2", 3", or even 4" for the small wheel and 4", 6", 8", 10" or even 12"
for the larger wheel. Sample breakdown is for a 2" and an 8".

1.5"x1.5"x18" solid square bar (price for this example breakdown is for a 24" piece from onlinemetals.com)

$34.22

1

Miscellaneous nuts, bolts, washers

$20.00

Total:

$891.69

The GIB is designed to use a 56 frame motor. It does not
need a base on the motor, but it does help a little with stability.

The entire kit can be built for less depending on how much time spent scavenging is done. Sample breakdown assumes all new components.

The Grinder in a Box can be setup
with a 3ph motor and a VFD for variable speed control. While this
is nice, it is not always necessary and the grinder will still work
great with a single speed. Your needs will dictate which is
better.

You can also mount a single large wheel (10"
for example) on a tooling bar. The small wheel adaptor from
USAknifemaker will also work on a bar with this kit.